The invention relates to a multi-functional surgical instrument for performing orthopedic surgical resectioning, total joint replacement and fixation of fractures. The invention also relates to a method of resectioning the femur and/or tibia bones in preparation for implantation of a knee prosthesis.
Surgical manipulation of joints and bones requires efficient and accurate instruments adaptable to an individual patient. Such surgeries directly affect the alignment of the patient""s bones and the function of related joints which, in turn, impact the patient""s pain, range of motion, ambulation and more. Surgical instruments have been developed to assist surgeons in performing orthopedic surgeries, such as the reconstruction of fractured bones, the preparation of bones and the implantation of total joint prostheses. These surgeries involve delicate procedures that are necessary to enable patients to move properly and without pain. The accuracy of surgical cuts to the patient""s bones is important in assuring proper bone alignment and the best possible fit and alignment of any implanted prostheses. Moreover, it is important to the success of the operation that the number of surgical manipulations be reduced to shorten surgical time, prevent blood loss or infection, reduce anesthesia and eliminate further violation or manipulation of soft tissue or bone.
A typical orthopedic surgical instrument used for resectioning joint surfaces during knee surgery involves mounting a cutting fixture to a patient""s femur to determine where to make cuts to the femur and/or adjacent tibia. These devices provide surgical references used for cutting the distal end of a femur and/or the proximal end of an adjacent tibia to create a surface to implant a knee prosthesis. However, these instruments typically have limited adaptability to the patient""s anatomy and require significant skill by multiple individuals to perform the proper cuts. Furthermore, such instruments also involve complex parts difficult for one person to manipulate, particularly under time restricted surgical conditions. As with any surgery, the amount of time a patient remains in an orthopedic surgery impacts the patient""s safety, recovery and medical expenses.
Another typical surgical instrument used in orthopedic surgery involves a rod insertable into the medullary cavity of a bone. These rods are driven into the medullary cavity and used to support a cutting fixture to determine the position and angle of cuts to the bone. However, these rods are unable to self-align within the femur to obtain the optimum alignment to the patient""s skeletal structure. Intermedullary rods have been developed that are capable of expanding into the surrounding bone to align and fix the bone. However, these devices fail to conform to the internal dimensions of the medullary cavity, optimize alignment within the bone or provide a single surgical reference point capable of supporting a cutting fixture alignable to the patient for performing multiple orthopedic surgical procedures.
For the foregoing reasons, there is a need for a surgical instrument which would offer relatively high accuracy while providing adjustability to the individual patient. Preferably, the instrument would be capable of performing multiple surgical manipulations based on a single reference point to the patient to enhance accuracy and repeatability. It would be further preferable to provide an instrument that performs multiple functions based on a single fixed support thereby eliminating the need for additional procedures and reducing surgical time, preventing blood loss or infection, reducing anesthesia and eliminating further violation or manipulation of soft tissue or bone. It would be more desirable if the instrument involved minimum complexity so that it can be easily manipulated and implemented. It would also be more desirable to reduce the number of instruments and procedural steps necessary to perform such surgical manipulations.
The foregoing needs are met by providing a multi-functional surgical tool with various components capable of performing multiple orthopedic surgical functions. The invention relates to an expandable Intermedullary support alignable within a medullary cavity of a bone. The support comprises a rod, a plurality of longitudinal roller bearings and a shaft. The rod has a tapered portion defining a longitudinal axis and terminating at a first end thereof. The rod is axially insertable into the medullary cavity and has an outer surface adapted to engage the bone. The rod also has a plurality of longitudinal slots positioned radially about the rod.
The plurality of longitudinal roller bearings are located in a longitudinal slot and movable therein between a collapsed position and an expanded position. At least a portion of each roller bearing is extendable beyond the outer surface of the rod in the expanded position.
The shaft is located in the rod and axially drivable therein. The shaft is adapted to engage the roller bearings. Axial advancement of the shaft moves the roller bearings to the expanded position thereby extending the roller bearings into the bone whereby the support is anchored therein in coaxial alignment therewith. Axial retraction of the shaft moves the roller bearings to the collapsed position thereby releasing the roller bearings from the bone whereby the support is axially removable from the medullary cavity of the bone.
The invention also relates to an orthopedic surgical instrument for resection of a distal end of a femur and a proximal end of an adjacent tibia in preparation for implantation of an orthopedic joint replacement. The instrument comprises an intermedullary support, a cutting guide, a tibial guide and a tibial locking arm. The intermedullary support comprises an alignment rod having a tapered portion terminating at a first end thereof and defining a longitudinal axis therethrough. The rod is axially insertable into the distal medullary cavity of the femur and has an outer surface adapted to engage the femur whereby the rod is alignable within the femur and provides a surgical reference point. The rod has a second end extending a distance beyond the distal femur.
The cutting guide is adjustably mountable to the second end of the rod and positionable about the distal end of the femur. The cutting guide has a plurality of femoral blade slots therethrough. Each femoral blade slot is adapted to operatively receive a blade whereby the blade is guided to perform osteotomies.
The tibial guide is adjustably mountable to the second end of the rod and positionable about the proximal end of the tibia. The tibial guide has a plurality of tibial blade slots therethrough. Each tibial blade slot is adapted to operatively receive a blade whereby the blade is guided to perform osteotomies. The tibial locking arm is slidably movable along the tibial guide and adapted to engage the proximal end of the tibia whereby the tibia is secured relative to the femur.
The invention also relates to a surgical instrument for orthopedic resection of a bone. The instrument comprises an intermedullary support and a cutting guide. The intermedullary support comprises an alignment rod, a plurality of longitudinal roller bearings, and an internal shaft. The alignment rod defines a longitudinal axis and has a tapered portion terminating at a first end thereof coaxially insertable into the medullary cavity of the bone and a second end extending beyond the bone. The tapered portion has an outer surface adapted to engage the bone and defines a plurality of longitudinal slots therethrough positioned radially thereabout. Each roller bearing is located in a longitudinal slot and movable therein between a collapsed position and an expanded position. The internal shaft is axially movable within the rod and adapted to engage the roller bearings. At least a portion of each roller bearing extends a distance beyond the outer surface of the rod in the expanded position. Axial advancement of the shaft moves the roller bearings to the expanded position thereby extending the roller bearings into the bone so that the support is anchored therein in coaxial alignment therewith whereby the rod provides a surgical reference point.
The cutting guide is adjustably mountable to the second end of the rod and positionable about an end of the bone. The cutting guide having a plurality of blade slots therethrough, each blade slot adapted to operatively receive a blade whereby the blade is guided to perform osteotomies.
Finally, the invention relates to a method of resectioning a distal end of a femur and a proximal end of an adjacent tibia in preparation for implantation of orthopedic joint replacements. The method comprises several steps: The expandable intermedullary alignment rod is inserted into the distal medullary cavity of the femur. The rod has a second end opposite the first end, the second end thereof extending beyond the medullary cavity to provide a surgical reference point. The rod is expanded into the bone whereby the rod is alignable thereto and securable therein. A tibial guide having tibial blade slots therethrough is mounted to the second end of the rod. A locking arm is slidably positioned along the tibial guide adjacent the proximal end of the tibia whereby the tibial guide is secured adjacent the tibia and the tiba is secured relative to the femur. A surgical blade is inserted into the tibial blade slots whereby the blade is guided to perform osteotomies. An adjustable cutting guide having femoral blade slots therethrough is mounted onto the second end of the rod adjacent the distal end of the femur. The blade is inserted into the femoral blade slots whereby the blade is guided to perform osteotomies.